2、SpringBoot+Mybatis整合------一对一
开发工具:STS
代码下载链接:https://github.com/theIndoorTrain/SpringBoot_Mybatis01/tree/93398da60c647573645917b27bd549da2f9f0f15
前言:
上一篇blog里面介绍了整合springboot和mybatis的项目的建立,以及单表的简单的增删改查。这里是上一篇blog的地址:https://www.cnblogs.com/TimerHotel/p/springboot_matatis_01.html。今天我们来介绍一对一的关系该怎么处理。
一、建立数据库:
每个学生对应一张身份证,每张身份证上有身份证号cardId、开始日期、结束日期。并且建立与student表的外键关系
二、代码实现
1.添加身份证实体:
package com.xm.pojo;
import java.util.Date;
/**
* 身份证实体
* @author xm
*
*/
public class IDCard {
private int sid;
private long cardId;
private Date beginTime;
private Date endTime;
private Student student;
public Student getStudent() {
return student;
}
public void setStudent(Student student) {
this.student = student;
}
public int getSid() {
return sid;
}
public void setSid(int sid) {
this.sid = sid;
}
public long getCardId() {
return cardId;
}
public void setCardId(long cardId) {
this.cardId = cardId;
}
public Date getBeginTime() {
return beginTime;
}
public void setBeginTime(Date beginTime) {
this.beginTime = beginTime;
}
public Date getEndTime() {
return endTime;
}
public void setEndTime(Date endTime) {
this.endTime = endTime;
}
}
IDCard.java
2.添加数据操作接口mapper:
package com.xm.mapper;
import java.util.List;
import com.xm.pojo.IDCard;
/**
* Idcard的数据操作层接口类
* @author xm
*
*/
public interface IDCardMapper {
/**
* 获取包括学生信息的身份证列表
* @return
*/
public List<IDCard> getListIdOfStudent();
}
IDCardMapper.java
3.添加mapper映射:
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd" >
<mapper namespace="com.xm.mapper.IDCardMapper">
<!-- 学生表与身份证表的一对一映射-->
<resultMap type="iDCard" id="IDCardOfStudentMap">
<id property="cardId" column="cardId"/>
<result property="beginTime" column="begin_time"/>
<result property="endTime" column="end_time"/>
<association property="student" javaType="student">
<id property="id" column="id"/>
<result property="name" column="name"/>
</association>
</resultMap>
<!-- 查出带有学生信息的身份证列表 -->
<select id="getListIdOfStudent" resultMap="IDCardOfStudentMap">
select * from id_card a,student b where a.sid=b.id;
</select>
</mapper>
IDCardMapper.xml
4.添加controller
package com.xm.controller;
import java.util.List;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;
import com.xm.mapper.IDCardMapper;
import com.xm.pojo.IDCard;
/**
* 身份证信息的控制类
* @author xm
*
*/
@RestController
public class IDCardController {
@Autowired
private IDCardMapper iDCardMapper;
/**
* 查出带有学生信息的身份证列表
* @return
*/
@GetMapping("/IDCardsOfStudent")
public List<IDCard> listOfStudent(){
List<IDCard> iDCards= iDCardMapper.getListIdOfStudent();
return iDCards;
}
}
IDCardController.java
三、测试:
1.数据表信息:
2.运行结果:
2018-06-19